Nmap Development mailing list archives

Re: Ncat accepting connections without --keep-open


From: Shinnok <admin () shinnok com>
Date: Sun, 19 Jun 2011 01:14:07 +0300

On 06/13/2011 10:50 PM, David Fifield wrote:
On Mon, Jun 13, 2011 at 06:56:55PM +0300, Shinnok wrote:
Off-topic question: In the context of ncat issues without --keep-open,
the server doesn't really block new incoming connections, instead it
accepts them and quits as soon as one of the connections is closed. Is
this the desired/planned behavior? Wouldn't it be more *correct* if we
refuse any further connections just like nc(netcat) does, when not in
brokering/keep-open/chat modes?

Yes, it sounds like Ncat should close its socket after accepting its
first connection. Would you write a test for how it's supposed to work?

David Fifield

Should closing the socket take effect in case of --max-conns also? Or
allow just the number of connections specified and then close as soon as
that number is achieved?

Eg. from the man page for context:

--
Bind a shell to TCP port 8081, limit access to hosts on a local
network and limit the maximum number of simultaneous connections
to three

ncat --exec “/bin/bash” --max-conns 3 --allow 192.168.0.0/24 -l
8081
---

The above examples doesn't specify --keep-open.

Regards,
Shinnok
_______________________________________________
Sent through the nmap-dev mailing list
http://cgi.insecure.org/mailman/listinfo/nmap-dev
Archived at http://seclists.org/nmap-dev/


Current thread: